Fair value of financial instruments - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Sep. 30, 2021	Jun. 30, 2021
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	$ 105,300	$ 58,100
Common Stock, Shares Issued	61,730,816	48,511,735			878,098
Issuance of common stock, value	$ 62	$ 49
Harvard and Board
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Success payment liability, payable	$ 10,000,000	10,000,000
Success payment, current portion				$ 6,300
Broad License Agreement
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Common Stock, Shares Issued	276,075
Fair value inputs probability of termination			90.00%
Maximum | Harvard
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Success payment liability, payable		31,300
Other Expense
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Success Payment Liability, Payable	$ 1,500	$ 7,800	$ 2,400